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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Behavior of Prestressed Concrete Bridges with Closure Pour Connections and Diaphragms

Ramos, Gercelino 29 October 2019 (has links)
Accelerated Bridge Construction (ABC) has gained substantial popularity in new bridge construction and bridge deck replacement because it offers innovative construction techniques that result in time and cost savings when compared to traditional bridge construction practice. One technology commonly implemented in ABC to effectively execute its projects is the use of prefabricated bridge components (precast/prestressed bridge components). Precast/prestressed bridge components are fabricated offsite or near the site and then connected on-site using small volume closure pour connections. Diaphragms are also commonly used to strengthen the connection between certain prefabricated components used in ABC, such as beam elements. Bridges containing closure pour connections and diaphragms can be designed using AASHTO LRFD live-load distribution factor formulas under the condition that the bridge must be sufficiently connected. However, these formulas were developed using analytical models that did not account for the effects of closure pours and diaphragms on live-load distribution. This research study investigates live-load distribution characteristics of precast/prestressed concrete bridges with closure pour connections and diaphragms. The investigation was conducted using finite element bridge models with closure pour joints that were calibrated using experimental data and different configuration of diaphragms. The concrete material used for the closure pour connections was developed as part of a larger project intended to develop high early-strength concrete mixtures that specifically reach strength in only 12 hours, a critical requirement for ABC projects.
112

Plasticité cérébrale dans le système olfactif : étude du modèle des sommeliers

Poupon-Pourchot, Daphnée 05 1900 (has links)
Cette thèse s’intéresse à la capacité du cerveau à s’adapter à un environnement changeant. Plus spécifiquement, elle s’intéresse à la plasticité cérébrale dans le système olfactif. Les sommeliers, experts dans le domaine de l’olfaction, ont constitué notre modèle. Une première étude nous a permis d’établir un protocole afin de tester la performance olfactive des sommeliers. Dans une deuxième étude, nous avons testé des étudiants en sommellerie au début de leur formation d’un an et demi qui mène à la profession de sommelier. Nous avons observé que ces futurs experts de l’olfaction présentaient déjà, au cours des deux premiers mois, des capacités olfactives supérieures. Dans une troisième étude, nous avons de nouveau testé les étudiants à la fin de leur formation, afin d’examiner les effets d’un entraînement olfactif à long terme sur la performance olfactive et sur le cerveau : en plus de mesurer les capacités olfactives avec le test des Sniffin’ Sticks, nous avons utilisé l’imagerie par résonance magnétique (IRM) pour évaluer l’évolution du cerveau au cours de la formation en sommellerie. Nos principales observations concernent des changements au niveau de la structure cérébrale. Premièrement, le volume du bulbe olfactif a augmenté au cours de la formation, ce qui est en accord avec la littérature disponible à propos de cette structure. Deuxièmement, nous avons observé un épaississement au niveau du cortex entorhinal mais aussi un amincissement au niveau d’autres régions du cortex. Mises en relation avec les résultats d’études antérieures, ces observations soutiennent le récent modèle de surproduction-élagage selon lequel les changements dus à la plasticité liée à l’entraînement ne sont pas linéaires mais font intervenir différents processus en plusieurs phases. Ce modèle constitue une avancée importante dans la compréhension des mécanismes impliqués dans la plasticité cérébrale et devrait être pris en compte dans les futures études sur la plasticité. Bien que les résultats sur le plan neuroimagerie soient intéressants, les résultats de l’étude longitudinale relatifs à la performance olfactive n’étaient pas concluants sur le plan comportemental. Nous avons donc mis en place dans une quatrième étude une tâche d’identification d’odorants au sein de mélanges plus complexe et plus adaptée aux sommeliers qui a confirmé la supériorité de leurs capacités olfactives. Nous avons aussi entraîné des novices sur cette tâche pendant cinq jours pour tester les effets d’un court entraînement olfactif. Cette thèse est organisée sous forme de thèse par articles. Le premier chapitre correspond à l’introduction générale, qui est elle-même organisée en plusieurs grandes parties. Ces différentes parties définissent les concepts-clés de cette thèse : l’olfaction, les corrélations neuroanatomiques dans le système olfactif, la plasticité cérébrale, la plasticité liée à l’entraînement dans le système olfactif, la neuroimagerie. La dernière partie conclut l’introduction en présentant les objectifs et hypothèses de recherche. Les chapitres suivants correspondent aux articles rédigés au cours du doctorat et présentant les résultats des recherches. Le dernier chapitre constitue une discussion générale. Enfin, en annexes se trouvent deux articles publiés lors du doctorat, un chapitre à paraître dans un livre ainsi que des résultats non publiés. / This thesis is about the brain’s ability to adapt to an ever-changing environment. More specifically, it is about brain plasticity in the olfactory system. We used sommeliers, who are experts in olfaction, as our model. A first study allowed us to instate a protocol to assess sommeliers’ olfactory function. In a second study, we tested sommelier students at the start of their year-and-a-half-long training which is the prerequisite to become a professional sommelier. We observed that these future experts in olfaction already had, during the first two months of training, superior olfactory abilities. In a third study, we tested sommelier students again at the end of their training to examine the effects of a long-term olfactory training on olfactory performance and on the brain: beside assessing olfactory performance with the Sniffin’ Sticks test, we used magnetic resonance imaging (MRI) to examine the evolution of brain structure and function during sommelier training. Changes in brain structure constituted our main results. Firstly, olfactory bulb volume increased during sommelier training, which is in line with previous reports about this structure. Secondly, we observed a cortical thickness increase in the entorhinal cortex but also cortical thinning in other brain areas. Put together with findings from previous studies, these results support the recent overproduction-pruning model of plasticity according to which changes due to training-related brain plasticity are nonlinear but involve different processes and different phases. This model constitutes a great advance in the understanding of brain plasticity and its underlying mechanisms and should be considered in future studies about plasticity. Though neuroimaging results were interesting, results from olfactory tests in our longitudinal study were not conclusive so we conducted a fourth study to test the ability to identify odorants within mixtures, a task which is more complex and suitable for sommeliers than the Sniffin’ Sticks test. Sommeliers performed better. We also tested novices that we had trained on this task for five days to evaluate the effects of a short-term olfactory training. This thesis is organized by articles. The first chapter is a general introduction, itself organized in several parts. These different parts define the major concepts of this thesis: olfaction, neuroanatomical correlations in the olfactory system, brain plasticity, plasticity in the olfactory system, neuroimaging. The last part concludes the introduction with aims and hypotheses. The following chapters are articles written during PhD that present the results of our research. The last chapter is a general discussion of all the results. Finally, two articles published during PhD, a chapter that is to be published in a book and unpublished results are presented as appendices.
113

Řešení zastávek MHD na ulici Kounicova v Brně v prostoru křižovatky s ulicí Hrnčířskou / Design of public transport stops at Kounicova street in the area of the junction with the Hrnčířská street in Brno

Kolková, Nela January 2014 (has links)
Master's thesis presents design of public transport stops at Kounicova street in the area of the junction with the Hrnčířská street. There are important places of intersts without a direct connection to public transport. Included are three designs that were proposed depending on local conditions. Another part is the vision of a new layout Björnsen's orchard with a little precious trees and unpaved footpath, which is located in the center of academic institutions and therefore should perform representative function. The thesis also addresses the transport connection of the planned undereground garage next tu Björnsen's park.
114

Evaluating Security For An IoT Device

Shakra, Mohamed, Jabali, Ahmad January 2020 (has links)
IoT systems usage is rapidly growing, and is involved in many industries causing more potential security flaws to a freshly new field. Even light bulbs, have a new generation called smart light bulbs have taken a step into the IoT world. In this project an affordable and available light bulb has it’s security evaluated by using a well known attacks to test the device security. It was concluded that the studied light bulb was found to be secured by the array of penetration tests carried in this project. However, the methods used for evaluating the device can be applicable to any other IoT for any future security evaluation. / IoT-systemanvändningen växer snabbt och är involverad i många branscher som orsakar fler potentiella säkerhetsbrister i ett nyligen nytt fält. Även glödlampor, har en ny generation som heter textit smarta glödlampor har tagit ett steg in i IoT- världen. I det här dokumentet utvärderas en prisvärd och tillgänglig glödlampa genom att använda en välkänd attack för att testa enhetens säkerhet. Det drogs slutsatsen att den studerade glödlampan befanns vara säkrad genom den mängd penetrationstester som utfördes i detta dokument. Metoderna som används för att utvärdera enheten kan dock tillämpas på vilken annan IoT som helst för framtida säkerhetsutvärdering.
115

Comparative Analysis of Physiological Measurements and Environmental Metrics on Predicting Heat Stress Related Events

Barlow, McKenzie Lee 01 June 2018 (has links) (PDF)
Exposure to high heat and humidity can lead to serious health risks, including heat exhaustion and heat stroke. Wet Bulb Globe Temperature (WBGT) and heat index have historically been used to predict heat stress events, but individualized factors are not included in the measurement. It has been shown that there is a relationship between cardiovascular measurements and heat stress, which could be used to measure heat stress risk on an individual level. Research has been done to find relationships between cardiovascular metrics in a workplace environment, however the study did not include the use of a controlled environment as a baseline. This study provides measurements of transepidermal water loss (TEWL), heart rate, body core temperature, and blood pressure in a controlled environment when human subjects are exposed to high heat and humidity. Thirty subjects (n=17 females, 13 males) were asked to self-express their activity level (active vs. sedentary), gender, and age. The subjects performed a 30-minute moderate exercise routine on a stationary stepper machine in a heated environmental chamber (average WBGT of 26ºC). TEWL, heart rate, tympanic temperature, and blood pressure were recorded at every 10-minute increment of the exercise protocol per subject. The data was analyzed using JMP® software to find significant (P
116

Circadian Clocks in Neural Stem Cells and their Modulation of Adult Neurogenesis, Fate Commitment, and Cell Death

Malik, Astha 23 July 2015 (has links)
No description available.
117

Cellular Function and Structure of Primary Cilia

Mohieldin, Ashraf M. January 2015 (has links)
No description available.
118

Embedded

Purdie, Christopher Dennis 18 July 2012 (has links)
No description available.
119

Inte en glödlampa LED-armatur 35000 timmar till, Not a lightbulb LED luminaire 35000 hours more

Tell, Erik January 2014 (has links)
Uppsatsen behandlar belysningsarmaturer inom LED-segmentet. Uppsatsen behandlar isynnerhet varför ljuskällan i LED-belysningsarmaturer oftast konstrueras så att ljuskällorna inteär utbytbara.Metoder som har använts i förstudien har varit; informationssökning, kvalitativa intervjuer,teknisk LED-modulsinventering samt konstruktionsundersökningar. Metoder som använts iproduktutvecklingsfasen har varit; tekniska informationsstudier, Idéinventering genom visuellidégenerering, imageboards och skissprocess (att tänka med en penna).Syftet med projektet har varit att utveckla en LED-armatur med utbytbar ljuskälla. Projektetsresultat blev en LED-golvarmatur med utbytbar ljuskälla. Ljuskällan som används i armaturenär enligt den unga branschfrivilliga standarden för LED-moduler, Zhaga. / The essay deals with luminaries in the LED segment. The essay deals in particular with why thelight sources in LED lighting fixtures usually is designed so that the light sources are notreplaceble.Methods used in this work has been; information searching, qualitative interviews, technicalLED module inventory and construction surveys. Methods used in the product developmentphase have been; technical information studies, Idea inventory by visual idea generation, imageboards and sketching process (thinking with a pen).The aim of the project was to develop an LED fixture with a replaceable light source. The resultof the project became an LED floor fixture with replaceable light source. The light source usedin the luminarie is of the young voluntary industry standard for LED modules, Zhaga.
120

Illuminating threats : Exploring cybersecurity threats in smart bulbs and illuminating a path to enhanced protection

Formosinho, Francisco January 2024 (has links)
There are serious security risks with the growing use of IoT devices. Historically, manufacturers prioritized profit over security due to high demand, a perspective that has evolved but remains a challenge. With this, the security of IoT devices has been overlooked, especially regarding smart bulbs, as they tend to be bundled with other IoT devices by the research community, and consequently not receive the attentionthey require. This thesis aims to identify and analyze potential threats regarding smart bulbs, and it does so by exploring proactive strategies in order to mitigate vulnerabilities. To understand the challenges smart bulbs face, some of the current applicable legislation, cyber attacks, defense mechanisms, and vulnerabilities were analyzed. Then, a network topology and a data flow diagram of a home network with smart bulbs was developed. Consequently, layers were assigned to the smart bulb, and threat modeling was performed on a each layer using STRIDE. This procedure was then formalized with a framework that encapsulates the stages of analysing the smart bulb’s landscape through threat modeling. This work contributes to the research community’s body of knowledge by providing valuable insights detailing the smart bulb’s landscape, not only through the framework but also through the conducted threat modeling, the data flow diagrams, and the information gathered regarding the threats to smart bulb security.

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